Improvement in breech-loading and other fire-arms



J. W. COCHRAN.

Breech-Iqading Fire-"arm N0 26 256 Pal tented Nov 29, 1859.

UNirnn. STATES PATENT @rricn.

JOHN VEBSTER GOOHRAN, OF NEW YORK, N. Y.

Specification forming part of Letters Patent No. 26,256, dated November 29, 1859.

To aZZ whom it may concern:

Be it known that I, JOHN WEBSTER Coon- RAN, of the city, county, and State of New York, have invented certain new and useful Improvements in Fire-Arms; and I do hereby declare that the following is a full, clear, and exact description of the same, reference be. ing had to the accompanying drawings, forming part of this specification, in which- Figures 1 and 2 are central longitudinal sec tions, at right angles to each other, of a breechloading cannon with my improvements. Fig. 3 is a side view of the movable breech-piece. Fig. 4 is a rear view of the gun with the breechpiece removed. Fig. 5 exhibits a side view of what I call the plunger of the breech,

and a central section of what I call an accelerating-cartridge. 7

Similar letters of reference indicate corresponding parts in the several figures.

' My invention, though it may be wholly or in part applicable to ordnance and small-arms of all kinds, either breech-loading or muzzleloading, is more particularly designed for breech-loading ordnance. The nature of the invention consists in a certain construction of and modeof applying the breech, and mode of combining therewith a spring or elastic cushion, which yields to the force so suddenly developedbythe explosion of the charge, by which the following results are produced, viz: First, the projectile is started gently, and the great strain that is produced in the chamber of a gun with a rigid breech before and during the starting of the projectile is obviated and recoil is in a great measure prevented second, a more perfect combustion of the powder is effected; third, provision is made for lubricating the chamber, breech, and bore of the gun; and, fourth, one or more accelerating-chambers are provided to contain charges of powder, for the purpose of giving additional impetus to the ball after it has fairly started.

To enable others to make and use my invention, I will proceed to describe its construction and operation. v

A is the gun, which is bored right through, and counterbored from the rear, to receive the hollow breech-piece B and solid sliding breechpin or plunger 0. The front portion of the plunger 0, which enters the rear portion of the bore 6 e of the gun, is turned sufficiently small to enable the thickness of the shell of the accelerating cartridge D, Fig. 5, to be received between it and the bore of the gun. The rear portion of the said plunger-is made cylindrical and somewhat larger than the front portion, and fitted snugly, but easily, into a centrally and cylindrically bored chamber in the breech-piece B, and between the portion which fits the bore of the gun and the portion which fits the bore of the breech-piece there is a collar, a, on the said plunger, which fits into the cylindrical front portion, 1) b, of the counterbore ofthe gun. indispensable, as the cylindrical portion 1) b of the counterbore may be made of the same size as the cylindrical bore of the breech-piece B, provided it is sufficiently larger than the bore 6 e of the gun to permit the formation of the accelerating-chamber c 0, Fig. 1, which will be presently described.

Vithin the bore of the breech=piece B, and in rear of the pin 0, is placed the spring D, of the conical volute kind, which is the only kind that can be madepracticable for the purpose, said spring being of very great strength,

and being so applied as to prevent its eXpan sion laterally, so that it will yield only with great force, and yield slowly to the action of the force of the explosion of a charge of powder on the front end of the plunger. The front portion of the breech-piece B is fitted snugly but easily within a cylindrical portion, (Z (Z, of the counterbore in rear of the part b b, and the rear portion of the said breech-piece is fitted to turn freely in a ring or circular frame, E, which is hinged by a hinge, j, to a slide, F, which works in a groove in one side of the gun, said slide being intended to be operated bya rack and pinion or any other suitable contrivance, to permit the ring E to be moved back far enough to withdraw the breech-piece longitudinally from the .gun before moving it aside, as shown in Fig. 2, and

in red outline in Fig. 1, to permit the introduction of the projectile and the principal cartridge through the open breech of the gun. The breech-piece may be secured in its place in the gun by being secured in with a complete screw-thread; but I have represented it as being constructed with two lugs, g g, which are capable of passing through suitable recesses, h h, Fig. 4, in the sides of a bushing,

This collar a is not, however, i

- celerating-chamber c c.

G, which is screwed into the open rear of the gun. In front of this bushing a recess, z z, is provided all around the counterbore of the gun, to permit the breech-piece to be turned to bring the rear faces of the lugs g g, which are made inclined so as to have a screw-like character, into. contact with the correspondently-incline'd front face of the bushing,for the purpose of forcing up the valve dike front end of the breech-piece B close up to the seat j j, that is formed for it between the portions I) b and (Z d of the counterbore. The bushing G may not be indispensable, as the portion of the gun which the bushing forms may be made of the solid metal; but the bushing' being screwed in allows it to be adjusted to make the joint at j j perfectly tight and tocompensate for any wear at the said joint.

The accelerating-chamber c c, which I have before spoken of, is formed between the exterior of the plunger 0 of the breech and the interior of the front and smaller portion, 1) b, of the counterbore of the gun, as shown in Fig. 1, where the spring D is shown in its normal condition and the plunger in its most forward position. This chamber might be charged with loose powder; but as this mode of charging might be liable to someobjections, I place the charge of powder for the said chamber in the cartridge D (representedin Fig. 5.) The shell of this cartridge is made in the form of a cap to fit over the front end of the plunger of the breech; but the whole of the charge is contained in an annular chamber, 76 7.", formed round its rear, of such shape as to fill the ac- Two or-more accelerating-chambers may be provided in the same gun.

I will now proceed to describe the loading of the gun and the action and effects which take place in firing.

The breech-piece being turned to bring its lugs g g opposite the recesses h h, the slide F is run back far enough to permit the frame E with the breech-piece and plunger to be swung aside, out of the way of the bore, to permit the introduction thereinto of the projectile (shot or shell) H and the principal cartridge I into the chamber of the gun. This projectile and cartridge may be of any known or suitable construction. The accelerating-can tridge D* is put on over the front end of the plunger 0, while the breech-piece and plunger are out of the gun, and this being done and the projectile and principal cartridge having been put into the chamber, the breech-piece is swung back again and run into the gun and secured, and on the priming being applied to the vent Z, which communicates with the cartridge I, all is ready for firing. When the cartridge I explodes, the force so suddenly developed is exerted partly on the projectile and partly on the plunger C, and drives back the plunger upon the spring D, which slo wly yields and is compressed, thereby easing the starting of the ball and preventing the sudden and violent strain to which the breech and chamber of other guns, whether breech or muzzle load: of the charge. ing on the head of the accelerating-cartridge causes the latter cartridge to recede along with the plunder, and when they have receded so far that the head of the cartridge 0 and face of the plunger have passed beyond the bore 6 e, the fire enters the acceleratingchamber, and, destroying the thin fusible metal of which the front part of ,the said chamber 70 of the accelerating cartridge is composed, ignites the charge within said chamber, and causes the ball to derive another impact from the explosion of said charge. Before the projectile leaves the gun the pressure of the gas is so far reduced that the spring D is allowed to react upon the plunger and drive the latter forward, and hence the force expended in driving the plunger back is not lost, but all given out upon the projectile.

The shell of the accelerating-cartridge, being made of soft metal, constitutes a very effective packing to prevent gas passing by the collar (1 or corresponding shoulder ofthe plunger, said shell being driven back against the said collar and shoulder, and caused to expand outwardly against the sides of thechamber c 0 both by the force of the explosion of its own charge and by that of the charge in the cartridge 1.

The plunger 0, besides constituting an elastic cushion, as above described, acts as a safety-valve in case of the charge in the accelerating-chamber becoming accidentally ignited, for the force of the explosion acting upon the front of the collar a or corresponding shoulder drives back the plunger until.

the fire reaches the principal cartridge and the gun is discharged instead of being exploded.

To provide for the lubrication of all parts of the gun, I propose to introducev every time the gun is loaded, or as often as may be desirable, to the interior cavity, at m, of the breech-piece a quantity of water, not sufficient to interfere with'the operation of the plunger and spring. Whenthe plunger is driven back, a small quantity of this water is caused to pass between it and the sides of the breech-piece into-the accelerating-chamber and into the bore 6 6, thereby not only effecting lubrication of the parts, but extinguishing any sparks that may be left by the explosion. The water thus introduced also constitutes a packingbetween the breech-piece and plunger to prevent any gases getting into the chamber at m.

The plunger 0 and spring D may be applied to muzzle-loading guns, and a similar accelerating-chamber, c 0, may be provided in such guns 5 but such chamber, owing to the difficulty or impossibility of introducing a cartridge, must be loaded with loose powder by a suitable opening provided for the purpose.

-I do not claim, broadly, the invention of applying an elastic cushion in the breech of a gun, as I am aware that such a contrivance has been employed; nor do I claim the invention of accelerating-chambers so applied to' are subject at'the instant of the explosion The force of the explosion actfire-arms that the.charges contained therein 1 are fired after the ball has started; but

WVhat I claim as my invention, and desire to secure by LettersfPatent, is

1. So constructing and applying one or more acceleratingchambers, in combination with the plunger or elastic cushion, that the charge or charges in the accelerating chamber or chambers are fired by the driving back of the plunger or cushion, and that: the plunger or cushion serves as a safety-valve to the accelcrating-chambers,substantially as herein described.

2. Combining the movable breech-piece B, containing the plunger or elastic cushion, with a ring or circular frame, E, hinged to a slide, F, which works longitudinally to the gun, the whole operating substantially as described.

the gun, and operating substantially as herein'x described J. W. OOCHRAN.

Witnesses:

OHs. M. HUGHES, MIoH. HUGHES. 

